Guang Zhi Tay

I did my first degree in Singapore at the Nanyang Technological University and graduated in the Course of Chemistry and Biological Chemistry. I was very involved with HPLC/MS and GC/MS during my internship and decided to pursue my further career by doing the AS:MIT MSc programme at the University of Warwick. The first half of the year was taught courses and I was particularly excited by when Mass Spectrometry was being taught I've chosen to do my research project in HDX-MS to probe protein structure.

My Project

Previous studies have shown that hydrogen-deuterium exchange (HDX) mass spectrometry (MS) with top-down electron capture dissociation (ECD) can be used to investigate the protein conformation and dynamics. Deuteration pattern on the backbone amide of the protein are retained when the proteins are transfer from solution phase to gas phase. The mass shift in ECD generated fragments in the absence of hydrogen scrambling indirectly indicates the location of intramolecular hydrogen bonding. Focus has shifted from the easy to work with soluble protein to the insoluble membrane protein. Membrane proteins get highly unstable and denature and aggregate rapidly once removed from their natural bilayer. But stabilization can be achieved by dissolving membrane protein in detergent micelles. This work shows the successful replication of the usability of HDX-MS in structural determination of ubiquitin. The novel aspect introduced here is the determination of the solvent exposed region of invariant chain trans-membrane (Ii) in artificial membrane created by detergent micelles.